Vaccine Associated Subacromial Bursitis

Intramuscular injection into the deltoid muscle of the upper arm is a common method of delivery for a variety of vaccines. Potential for injury exists if the vaccine is given in an incorrect location due to the proximity of nearby anatomical structures such as the subacromial bursa, long head of the biceps tendon, and axillary nerve among others. Within the past decade, there have been multiple reports of shoulder injury associated with vaccine administration. This report details a case of a 34 year old woman who presented with acute left shoulder pain and limited range of motion following the administration of a Tdap vaccination into her left upper arm. The patient indicated that she thought that the vaccine injection had been given abnormally high in the shoulder. Subsequent MRI imaging showed an increased T2 signal in the subacromial/subdeltoid space suggesting an inflammatory process in the subacromial/subdeltoid bursa consistent with subacromial bursitis. A guidance document provided by the Immunization Action Coalition indicates that intramuscular deltoid vaccines should be given “in the central and thickest portion of the deltoid muscle – above the level of the armpit and approximately 2–3 fingerbreadths (~2 ) below the acromion process.” The CDC’s Vaccine Administration Pink Book recommended a 1” to 1 ½” needle based on our patient’s female gender and weight. A 2006 study by Bodor and Montalvo found that the subdeltoid bursa extends distally from the acromion with a range of 3.0 to 6.0 cm (1.2 to 2.4 inches) and that its depth from the skin ranged from 0.8 to 1.6 cm (0.3 to 0.6 inches). Thus, the potential exists to inject vaccine into the subdeltoid bursa even with the recommended vaccine administration protocol detailed previously. Therefore, when evaluating a patient with complaints of shoulder pain and/or dysfunction, vaccine associated shoulder injury should be added to the differential diagnosis if the history reveals a recent upper arm intramuscular vaccination